Though high yields and titers could be achieved using A. flavus, aflatoxin production by this organism disqualifies it for industrial malic acid production. Consequently, several attempts have been made to produce malic acid using highly engineered model organisms, like Saccharomyces cerevisiae and Escherichia coli. An S. cerevisiae strain overexpressing pyruvate carboxylase, malate dehydrogenase, and a malate exporter and carrying a pyruvate decarboxylase deletion reached malate yields of 0.42 mol mol−1 on glucose at a productivity of 0.19 g liter−1 h−1